This invention relates to a masking stick tool comprising a solid material mask in stick form and a tube or sleeve which houses the solid masking material and through which the solid masking material is advanced. The masking material temporarily masks a surface from paint, varnish or other coatings by applying a temporary masking coating upon rubbing an exposed portion of the solid paint masking material directly onto the surface to be masked, and thereafter removing the masking coating onto which paint varnish or other coating has adhered or made contact. The mask and coating forms a skin, and may be removed by peeling the skin from the protected surface. The paint mask material may be formed and applied as a crayon, or housed, advanced and hand-applied as one would the contents of a lip balm type dispenser.
The present invention meets the need in the art by providing a solid material that renders a convenient and accurately applied paint mask for windows and other surfaces requiring masking protection from paint, varnish or other coatings. The invention""s ease, non-drip accuracy in application overcomes the disadvantages present in spraying, squeezing, rolling and brushing liquid paint and coating masks. Because the mask material and paint are simply peeled from the surface much like tape, yet without the difficulties that attend the application of tape to a surface. Nor does the use of this mask involve leave tacky residue associated with masking tape nor involve the hazards and damaging scratches associated with razor blades. A type of peelable mask is described in Jeri U.S. Pat. No. 2,365,705. A direct masking stick application as described in Van Tyle U.S. Pat. No. 6,022,582.
A mask dispensing process may be accomplished through the use of a variety of substances and still meet the masking needs of window painters. Methods had been developed to shield the glass from errant paint, including the use of plastic inserts, masking tape, liquid masks, and dabbing viscous substances such as petroleum jelly onto glass. Painters looked for three characteristics in their masking efforts: the mask had to be easy to apply, easy to remove, and provide an effective shield from adhering coatings. Existing masking techniques offer the required paint shielding but are difficult to use. For example, smearing petroleum jelly onto glass may offer an adequate shield from paint drips yet present an unacceptable application method due to the need for finger contact, inconsistent thickness, and likelihood the jelly would find its way onto the frame and mullions due to its paste-like consistency. Liquid masks drip and run. The current paint masking stick permits inadvertant paint to be removed by rinsing or wiping, but does not permit the self-shearing deposited film to be peeled off the protected surface.
A novel solid mask application process, dispenser and solid mask herein described offer clear advantages over traditional plastic inserts, masking tape, liquid masks, and dabbing viscous substances such as petroleum jelly onto glass. Advantages include 1.) even film thickness, 2.) uniform dispensing, 3.) regulation of amounts dispensed by adjusting hand/stick pressure, 4.) predictable film strip width, 5.) accurate non-drip spot mask and 6.) easy peel-off removal. Nor does the process require an intermediate applicator as with pens, brushes, sprays, or pastes, since a stick capitalizes on frictional dispensing and shears off predictable and uniform amounts of mask upon direct contact.
A preferred embodiment of this masking tool and process involves the painting of windows. Painting window frames is a tedious and time-consuming task as the painter desires to fully cover the window frame while avoiding getting the paint on the windowpane itself. Often windowpane glass is separated by narrow dividers known as mullions. The mullion is a slender member placed between adjacent panes of glass supported by a flange and held in place by putty, caulk or a narrow strip of wood that covers the outside edge of the glass adjacent the mullion. When window frames or mullions are painted, the paint which otherwise gets on the windowpane must be thoroughly removed.
Past efforts at keeping paint from getting onto the windowpanes had been accomplished by masking the glass with tape along the perimeter of the pane where glass meets frame or mullion so that the trim or frame material can be painted quickly and without regard to the juncture between glass and trim since any excess paint will be applied to the protective coating. However, applying tape is laborious and time consuming and removing the tape from the glass often presents problems, particularly where the tape hardens or becomes tacky. Where tape has not been employed, paint must be scraped off the glass typically with a razor blade. Another method of masking involves a triangular mask with an adhesive strip around the perimeter. The triangular mask is applied to the glass surface and overlapped to cover the entire surface with a portion of the mask. Portions that overlay the mullions would need to be cut off so as not to interfere with the painting of the frames. Another device provides a flexible narrow blade with a straight edge that contacts the mullion. The ends of the blade are cut at an oblique angle. Two adjacent blades join at a comer of the window. A rubber vacuum cup attaches to each of the blades for securing the blade to the glass. Another device has a spring clip that engages opposed mullions frictionally. The clip presses a cardboard paint shield firmly against the adjacent windowpane. Another device involves a fitting that permits the application of caulk along the perimeter of the pane which caulk may be peeled off subsequent to painting. Yet another window mask product consists of a razor blade mounted on a squeeze bottle containing a liquid paint mask composed of petroleum distillates, which mask is applied to the window""s perimeter through a sponge applicator pad and left to dry. After the mullions and frame are painted the paint and mask drippings are scraped off with the attached razor-type blade.
Each of the foregoing paint mask efforts is plagued with drawbacks. The triangular shield designed to fit over the glass must be cut to size and the overlaps of triangular sections leave gaps that allow paint to seep onto the glass. The blade-style shield alluded to are labor intensive and require accurate positioning of adjacent shields to protect the glass surface. The cardboard shield becomes damp with paint and losses its effectiveness to seat the glass from painting. A spring clamp must be inserted to hold the cardboard sheet to the window. The caulk applicator requires the costly purchase of caulk, the manipulation of a relatively cumbersome caulk applicator, caulk build-up within the applicator, and time-consuming cleanup following caulk application. The razor blade/squeeze bottle method suffers the disadvantage of dripping, it requires time to dry onto the protected surface prior to painting, its petroleum distillate composition is an irritant to skin and eyes, and the use of a razor blade to remove paint scratches treated and energy efficient glass.
Commercial efforts at paint masking include the use of masking tape, caulk, masking paper and liquid paint masks. The liquid paint masks are applied by spraying, sponging, brushing or rolling. Hand-held portable paint mask applicators include a hand-held masking machine which applies masking paper to a desired location, and a fitted nozzle for a caulk gun that permits a caulk bead to be pumped onto and along a window pane""s edge by means of a manual pump trigger. Accordingly, there is a need in the art for an improved mask for glass to prevent painting the glass while painting mullions.
The present invention represents such an improved mask and application and removal process. When masking windowpanes, the mask is dispensed as a film along the perimeter of a windowpane and thereafter peeled off along with any dripped paint. The paint mask comprises a solid stick, not unlike those found in crayons, lip balms and glue sticks. The stick may contain glycerin, glycol or other substances that mask and retard paint adhesion, and be of such rigidity that it shears off and leaves a film upon the glass by means of dragging the stick""s end along the glass"" surface. Following painting, the film disadheres and from the glass by peeling or sliding it from the protected surface. The solid paint mask may be: applied as a crayon, or housed and advanced thorough an applicator resembling a lip balm or glue stick dispenser and which may be manufactured from plastic or some similarly rigid material. The mouth of the applicator should have at least one corner whose angle measures a right angle or less so as to fit easily into angled window frames. The cap seals and protects the solid masking material housed within the container and doubles as a scraper which may be used to remove difficult paint drips. The container""s cap assumes a wedge shape, forming an acute angle at its tip so as to permit access into the corners to lift and edge of the peeelable mask for easy removal. The method of the present invention will be useful to painting contractors, homeowners, hobbyists, autobody servicers, or anyone who paints materials that are adjacent to glass-like surfaces rapidly and inexpensively, or who otherwise wish to temporarily mask and protect solid material surfaces from brushed paints and coatings or overspray.
The inventions novelty lies in its coating and peelable removal process whereby a solid mask material, in the course of rubbing it onto glass, shears away and thereby deposits a protective paint masking coating onto the glass and is thereafter peeled from the protected surface like a skin. Mask components including hygroscopic glycols, silicone, oil, and fatty acids may be used to ease the removal of a polymer skin and thereby permit the skin to be slid or peeled from the surface to be protected. Easy-removal of a mask and its adhering paint distinguishes the superior paint mask.
Successful Mask Characteristics
A successful paint masking stick will exhibit the following favorable characteristics:
1. Easy dispensing onto the surface to be protected.
2. Effectively shields the protected surface from or other coating,
3. Easy removal of the mask along with paint drips or paint overspray.
The present invention achieves the listed characteristics in the following way. A dispenser or crayon houses a solid (or in the case of a solid dispenser a gelled) paint mask material that is dragged across a surface and deposits a film that shields the surface from paint, coatings or other outer affection. A dispenser housing may be used wherein the masking substance advances through a tubular opening and is exposed such that it may come into direct contact with the surface to be protected. The dispenser is then grasped in the hand and the exposed masking substance is rubbed onto the surface to be protected. The masking substance must have properties that allow it to shear away when rubbed onto the surface and deposit a thin uniform film that will act a protective shield against paint, coatings or other affection. Since paint is brushed and rolled onto a surface, it is important that the mask film be able to withstand the friction of the roller or brush. Nor should the mask film disadhere from the surface and stick to the roller or brush, hence the mask film must be minimally tacky. Hence, the mask""s consistency be such that it 1.) will shear away and deposit a thin and uniform film 2.) adhere to the protective surface and resist movement, 4.) exhibit minimal tackiness and 5.) permit easy removal of the mask and adhering paint or coating.